1. Field of the Invention
This invention relates to an oscillating trough for shotblasting in which workpieces are turned over.
2. Description of the Prior Art
Generally, a conventional oscillating trough has a V-shaped bottom with an angle of about 120.degree.. (Refer to U.S. Pat. No. 4,319,624.) When a plate, cube, or the like is treated in this trough, a trough surface that contacts the workpiece must be rotated about 60.degree. to become upright so that the workpiece can be turned over. However, the rotation will bring the workpiece up to a high place. Thus when the workpiece falls therefrom, the impacts generated by hitting the lower surfaces cause problems such as scars, cracks and chippings. Furthermore, the workpieces that have thus fallen slide down along a slope, which is about 30.degree., and crush against an inner surface of the oscillating trough causing further dents, cracks, breaks, etc.
This invention has been created in view of the drawback, and one of the objects of the invention is therefore to provide an oscillating trough for shotblasting in which workpieces are subjected to substantially less scars, crack, chippings, etc.
Another object of this invention is to provide a reversibly rotating trough in a shotblasting machine that is arranged to decrease crashes between workpieces when they are discharged from the trough.
A further object of this invention is to provide a trough in a shotblasting machine that is arranged so that the angle of rotation and/or speed of rotation can be changed depending on the shape of the workpiece.